Process and apparatus for producing depth effect in photography



Feb. 8 1927.

J. w. PRossER PROCESS AND APPARATUS FOR PRODUCING DEPTHEFFECT INPHOTOGRAPHY Original Filed Dec. l. 1923 e? wm.

Patented Feb. e, 1927.A

l'fulmine STATES 1,616,636- PTENT OFFICE.

JOSEPH W. PIROSSEIt, 0F NEW YORK, N. Y.

PROCESS-AND APPARATUS FOR PRODUCING DEPTH EFFECT IN PHOTOGRAPHY.

Application filed December 1, 1923, Serial No. 61??,951.` Renewed J'uly2, 1926.

Some of the objects of this invention are to reproduce in either stillor moving plctures the effects of depth or perspective; and, in the caseof the projection of pictures,

b to produce an effect of softened lines which without loss of detailwill be pleasing to the eye and free of eye-straining inuences.,

A further importantpobject of the invention is to secure the desiredresults simply l and effectively and by inexpensive means applicable toapparatus in use at the present time.' l

n the accompanying drawing forming part of this specification there isillustrated F an embodiment and method of practising the invention, butas this illustration is primarily for purposes of disclosure, it will beunderstood that modifications of the same may be resorted to withoutdeparture from the broad spirit and s cope of the invention ashereinafter defined and claimed.

Figure 1 is a diagrammatic plan view v illustrating the action of thecamera in talring the picture, with the sensitized medium on which theimpression is made appearing in section. j g l Figure 2 is a sectionalview of the print orpositive taken from the negative.

Figure 3 is a vertical sectional view of the 3 gate structure of amotionpicture camera as equipped for securing the effects of thisinventlon. Y

Figure 4 isa front view of the same as it appears with the filmsupporting pad re-l moved.

The first step in the invention consists in supporting the sensitizedmedium 5, which 4 for convenience may be referred to herein as the filmwithin theA camera and while un- 0 der exposure, in an outwardly7 orforwardly bowed condition, as shown at the right in Figure 1.

To illustrate the effect of this, three objects '6, 7 and 8 areindicated at the left in this diagrammatic view, which objects might`for instance, be considered as the i trunks of three trees, one disposedin the center of the field of exposure and the others at the side, onelforward of and the other in v rear of the central object. The lens 9 ofthe camera may be `ofany usual or special form suited to transferringthe image to the sur-f face of the film. The light beam 11 defining 4thecentral ob'ect produces an image 12 at the center of t e film showingthis object as of substantially normal size. The light beams 13, lawhich define the side objects 7 and 8 are so inclined as to meet thecurved side portions of the film at more or less of a tangent, thedegree of approach to the tangential being dependent upon the curvature.a of the lm and the angle of the rays. `These dimensional rays are thusin edect spread out over the film a. distance greater than their actualwidth, producing on the curved surface of the film, images 15, 16,magnified or enlarged as compared to the image 12 of .the centralobject.

The sensitized layer 17A is of appreciable thickness and as `the lightraysenter and pass through this layer obliquely, it will be seen thatthe total impression produced by an object will be equal to the'distance between where the rays enter the face of the coating at anobtuse angle and leave at the opposite side at an acute angle, that isthe space represented at 17. n .v

This means that when the film is fiattened out, as indicated at 18y inFigure 1, or when a dat positive print is taken from the negative as at19 in Figure 2, the images 15', 16 vof the side objects will, because ofytheir accentuation, stand out in apparent relief, producing an illusionof perspective.- This increase in size when viewed in the final picturehas the effect of bringing the side' objects forwardly so that theobject 7 may appear as though it stood at 7 and the object 8 as thoughit were disposed at 8.

The results described may be effected in a practical and simple way byusing a flexible film such as employed for motion pictures and bybulging the same into convex form in the gate structure of the camera.

In Figures 3 and 4 this gate structure is indicated generally at 20 andthe means for imparting the ycurvature to the film is shown as a pad 21of felt or the like supported within the exposure aperature 22 over abolster 23 of rubber or the like, occupying the middle portion of theexposure space and formed as a mound rounded in alldirections so as toimpart a desired curvature .to the pad. The felt pad isnon-refiecting inits nature so as to form no reflections on the .overlaying curvedsection of film and at the same time forms a support over which the filmwill curve and return to fiat shape readily as it is fed forward by theadvancing mechanism. 11

In Figure i the bolster is indicated as of generally elliptical formhaving major and minor axes corresponding proportionately to the majorand minor 'axes of the oblong window or aperture of the gate structure..

ylhe operation of the invention should be clear from the foregoing, butit might be helpfull to a more complete understanding of the inventionto consider the fact that it is the relative sizes of objects inbinocular vision,'employing theprinciple of triangulation which is thebasis 'of udgment of distance or perspectivity. Hence when a portion ofa picture is enlarged as by the photographing on the curved' lm, anillusion of greater or less relative distance is created and a sense ofapparent depth or solidity is given. The curvature is made radual enoughso that there is no perceptible or objectionable distortion. It will beevident that when the film is curvedv to the rear at the top and-bottom,as well as toward the sides, the objects at the top and bottom of thepicture will also be accentuated but this degree of accentuation can be.reduced or varied by changing the degree or extent of curvature.

Another result of the oblique exposure of the negative to the light raysand the subsequent printing from such an oblique exposure is thesoftening of the lines of distinction which produces a very pleasingvartistic effect and relieves the eyes of strain or fatigue. l

Another fact resultingl from the photographing on the curved `film isthat there are two main focal distances, one, 24, between the lens andthe foremost section of the curved film, and a second, 25, between thelens and the rearmost part of the film.` The effect of this is that infocusing the furthest central objects, closer objects at the sides ofthe picture will also automatically be brought into perfect definition.The invention thus enables the taking of "innite and close-ups in properdefinition in the same picture.-

What I claim is:

1. The process of producing depth efiect in pictures which comprisesphotographing the object which is to be pictured al1 at once on the fullexpanse of a convexly curved sensitized medium and then reproducingacides@ for imparting a convex curvature to the full width section offilm held by the gate.

4. lin photography, a camera having a film-holding gate, means forimparting a curvature to thesection of film held by the gateandcomprising a bolster 'and a pad overlying said `bolster.

5. In photography, a camera having a hlm-holding gate, means forimparting a curvature to the section of film held by the gate andcomprising a bolster and a pad overlying said bolster, said bolsterbeing of a yielding nature and the pad having nonrefiecting resilientcharacteristics.

^`6. A motion picture camera having a filmholdinggate provided withmeans for imparting a forward bulge to the central portion of the filmheld in the field of exposure. 4

' 7 A motion picture camera having a filmholding gate with va stationaryforwardly curved convex film-supporting pad at thev back of the gateopening. 8. A camera havlng a fie d of exposure and provided with asta'- tionary curved non-reflecting pad for imparting a forward convexcurvature to the area of exposure of the curvedsensitized 'medium. y f

ln witness whereof, I have hereunto set my hand this 26th day ofNovember, 1923.

JOSEPH W. PROSSER.

holder for support. in the full Width of a'sensitized film in the--

